Preparation of the sponge of these high-melting-point high-toughness metals was formerly effected by using a separate apparatus respectively in the reduction step and the step of separation of the formed metal (vacuum distillation and condensation of the by-product). An apparatus combining the reduction chamber and the separation chamber was disclosed in Japanese Published Patent Publication No. 18717/72. Various improvements in such an integrated apparatus are disclosed in Japanese Published Patent Laying-Open Patent Publication No. 49922/77, etc.
All the known integrated apparatuses comprise a reaction (reduction) chamber and a condensation chamber located immediately thereabove, and all the improvements relate to the construction of the connecting part between the two chambers and the means for shutting off the connecting part. The apparatus of the copending application No. 485,057 now U.S. Pat. No. 4,470,045 has a connecting part which is shut off by a seal pot filled with a fusible and volatile material. With this arrangement, the two chambers can easily be separated even when the reaction chamber is still hot, so the reaction chamber can be removed from the heating furnace. Also this apparatus is advantageous in that the same container can be used as the reaction chamber as well as the condensation chamber.
In this apparatus, however, the produced spongy metal, from which the by-product has been removed, is taken out from the reaction chamber by tilting or turning the reaction chamber upside down. Also when a chamber is interchangeably used as the reaction chamber and the condensation chamber, a chamber which has been used as the reaction chamber must be turned upside-down by 180.degree. in order to be used as the condensation chamber. This is a significant inconvenience when larger capacity apparatuses are required.
When two chambers of the same shape are used as the reaction chamber and the condensation chamber, six kinds of arrangement of the two chambers are conceivable: a vertical arrangement of an upright reaction chamber and an upright condensation chamber placed right above the former; a vertical arrangement of an upright reaction chamber and an upright condensation chamber placed right under the former; a vertical arrangement of an upright reaction chamber and an inverted condensation chamber placed right above the former; a right angle arrangement of an upright reaction chamber and a horizontally positioned condensation chamber placed under the former and connected with an elbow connector crooked at 90.degree.; a right angle arrangement of an upright reaction chamber and a horizontally positioned condensation chamber placed above the former and connected with an elbow connector crooked at 90.degree.; and a parallel vertical arrangement of an upright reaction chamber and an upright condensation chamber.
Of these six arrangements, the third arrangement was employed in the apparatus of the copending application No. 511,934. So the first and the second arrangements are regarded as modifications of the invention of said application.
This invention provides an improved apparatus for preparation of high-melting-point high-toughness metals employing the above-mentioned last arrangement whereby the above-mentioned disadvantage of the prior art apparatuses is eliminated.